Gene expression changes in CD4+ thymocytes upon removal of Cullin3
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ABSTRACT: We report gene expression changes in Cul3 deficient thymic CD4+ T cells We used microarrays to detail the global programme of gene expression changes upon removal of Cul3 during thymic development
Project description:We report gene expression changes in Cul3 deficient thymic CD4+ T cells We used microarrays to detail the global programme of gene expression changes upon removal of Cul3 during thymic development CD25-, CD1dPBS57-, gdTCR - CD4+ Single positive cells from thymocytes of CD4Cre-Cul3fl/fl (LM) and CD4 Cre+Cul3fl/fl (KO) were sort purified and total RNA was extracted using Trizol and analysed by microarray.
Project description:This experiment uses a transgenic cell line expressing bacterial OGA BtGH84 fused to a localization peptide (NLS) and regulated by Tet-On system. OGA is a glycosidase that removes O-GlcNAc modifications. We evaluated the changes in chromatin openness before and after O-GlcNac removal by OGA.
Project description:This experiment uses a transgenic cell line expressing bacterial OGA BtGH84 fused to a localization peptide (NLS) and regulated by Tet-On system. OGA is a glycosidase that removes O-GlcNAc modifications. We evaluated the changes in gene expression before and after O-GlcNac removal by OGA.
Project description:Thymoma and thymic carcinoma represent the two most characterized types of Thymic epithelial tumors (TET) which arise from epithelial cell of thymus. According to the different morphological features, lymphocytes and epithelial cells ratio and grade of malignancy, TET are divided in thymoma A, AB, B1, B2, and B3 and thymic carcinoma. We used microarrays to detail the global programme of gene expression distinguishing tumoral and normal thymic tissue, thus identifying networks of correlated mRNAs-lncRNAs.
Project description:During mitosis, the genome is restructured to facilitate chromosome segregation, accompanied by dramatic changes in gene expression. However, the mechanisms that underlie mitotic transcriptional regulation are unclear. In contrast to transcribed genes, centromere regions retain transcriptionally active RNA Polymerase II (RNAPII) in mitosis. Here, we demonstrate that chromosome-localized cohesin is necessary and sufficient to retain active RNAPII on mitotic centromeres. Failure to remove cohesin from mitotic chromosome arms dramatically alters mitotic gene expression, and results in a failure to release elongating RNAPII and nascent transcripts from mitotic chromosomes. We propose that prophase cohesin removal is the key step in reprogramming gene expression as cells transition from G2 to mitosis, and is temporally coupled with chromosome condensation to coordinate chromosome segregation with changes in gene expression.
Project description:During mitosis, the genome is restructured to facilitate chromosome segregation, accompanied by dramatic changes in gene expression. However, the mechanisms that underlie mitotic transcriptional regulation are unclear. In contrast to transcribed genes, centromere regions retain transcriptionally active RNA Polymerase II (RNAPII) in mitosis. Here, we demonstrate that chromosome-localized cohesin is necessary and sufficient to retain active RNAPII on mitotic centromeres. Failure to remove cohesin from mitotic chromosome arms dramatically alters mitotic gene expression, and results in a failure to release elongating RNAPII and nascent transcripts from mitotic chromosomes. We propose that prophase cohesin removal is the key step in reprogramming gene expression as cells transition from G2 to mitosis, and is temporally coupled with chromosome condensation to coordinate chromosome segregation with changes in gene expression.
Project description:During mitosis, the genome is restructured to facilitate chromosome segregation, accompanied by dramatic changes in gene expression. However, the mechanisms that underlie mitotic transcriptional regulation are unclear. In contrast to transcribed genes, centromere regions retain transcriptionally active RNA Polymerase II (RNAPII) in mitosis. Here, we demonstrate that chromosome-localized cohesin is necessary and sufficient to retain active RNAPII on mitotic centromeres. Failure to remove cohesin from mitotic chromosome arms dramatically alters mitotic gene expression, and results in a failure to release elongating RNAPII and nascent transcripts from mitotic chromosomes. We propose that prophase cohesin removal is the key step in reprogramming gene expression as cells transition from G2 to mitosis, and is temporally coupled with chromosome condensation to coordinate chromosome segregation with changes in gene expression.
Project description:We utilized the Nematostella vectensis to quantify gene expression differences and loss during light:dark cycling and immediately after light cue removal through comparisons of 136 transcriptomes Organismal responses to light:dark cycles can result from two general processes: (i) direct response to light or (ii) a free-running rhythm (i.e., a circadian clock). Previous research in cnidarians has shown that candidate circadian clock genes have rhythmic expression in the presence of diel lighting, but these oscillations appear to be lost quickly after removal of the light cue. Here, we measure whole-organism gene expression changes in 136 transcriptomes of the sea anemone Nematostella vectensis, entrained to a light:dark environment and immediately following light cue removal to distinguish two broadly defined responses in cnidarians: light entrainment and circadian regulation. Direct light exposure resulted in significant differences in expression for hundreds of genes, including more than 200 genes with rhythmic, 24-hour periodicity. Removal of the lighting cue resulted in the loss of significant expression for 80% of these genes after one day, including most of the hypothesized cnidarian circadian genes. Further, 70% of these candidate genes were phase shifted. Most surprisingly, thousands of genes, some of which are involved in oxidative stress, DNA damage response, and chromatin modification, had significant differences in expression in the 24 hours following light removal, suggesting that loss of the entraining cue may induce a cellular stress response. Together, our findings suggest that a majority of genes with significant differences in expression for anemones cultured under diel lighting are largely driven by the primary photoresponse rather than a circadian clock when measured at the whole animal level. These results provide context for the evolution of cnidarian circadian biology and help to disassociate two commonly confounded factors driving oscillating phenotypes.